Skip to main content

Full text of "Flora Indica Vol-I"

See other formats

216                                     FLORA  TNDICA.
in contact The Tibetan Flora of the Indus, therefore, ends a
little below Iskardo, pines appearing in the district of Rondu,
and throughout the valley of Hasora, which latter may hence
be regarded as not Tibetan.
The mean elevation of Western Tibet exceeds that of all
countries of which we have any definite knowledge, and, if
not surpassed by part of Eastern Tibet, is without doubt the
loftiest area of any considerable extent on the surface of the
globe. Captain H. Strachey gives 15,000 feet as the approxi-
mate mean elevation; and when we consider that there are
throughout Tibet many ranges of a uniform elevation of 19-
20,000 feet, and peaks innumerable of 21-25,000, as also that
the very lowest level of the Indus valley (itself a mere cleft in
the mountain mass) is 6000 feet, the above estimate will not
be considered exaggerated. Of the passes over the main axis of
the Kouenlun and Himalaya, and over their principal ramifi-
cations, far more are above than below 17,000 feet, many arc
18,000, and a few 19,000; besides which many extensive areas
in Guge, Nari, Nubra, Rupchu, and Zanskar, are continu-
ously above 15,000 feet for many miles in all directions.
The climate of Western Tibet can only be approximately
ascertained, no continued records of temperature, humidity of
the air, or rain-fall, having ever been kept. Captain H. Stra-
chey has however reduced all the detached observations that
were procurable, and we are indebted to his valuable paper on
the Physical Geography of Western Tibet* for most of the
following data.
In the basin of the Indus at Lc, elevated 11,800-12,000
feet, and 1300-1500 above the bed of the river, which is con-
siderably below the mean elevation of Western Tibet, and
in a sheltered locality, the mean temperature of the year is
assumed to be 35°: of January 10° (variation -5° to 4-25°),
and of July 60° (variation 50° to 70°). Constant frost sets in
at that elevation early in November, and lasts till the eud of
February; but night-frosts continue till the middle of April,
# Bead before the Boyal Geographical &x»iety, Kov^mber, 1853,